Airbus Defence and Space


On-Board Computer Unit (OBC) for the on-board control system

A 16 bit integrated computer for on-board control systems


Derived from the Spacebus3000B On-Board Computers from Airbus Defence and Space, this Integrated Control and Data System Electronics is the central component of on-board control systems for LEO, MEO and GEO satellites with a lifetime of typical 10 to 15 years.

Based on the heritage of Globalstar and Spacebus3000B On-Board Computers, it features a modular design and implementation that allows it to be tailored easily to individual customer requirements.

Features / technical details

The On-Board Computer Unit (OBC) is the central component of the On-Board Control System for satellites. It is designed in a modular approach, which allows easy adaptation to the requirements of different applications.

The On-Board computer includes a Safeguard Memory, a Reconfiguration Module including a Watchdog circuit, the Surveillance Logic and the respective Command Interface in compliance with the reconfiguration strategy.

The On-Board Computer hardware supports the software necessary for Telemetry, Telecommand, Housekeeping, attitude and Orbit control, Failure Detection, Isolation and recovery (FDIR) with sufficient memory capacity, calculation power, clock stability and data protection.

The core of the system are two redundant 16-bit processor modules, implementing the P 1750A single chip CMOS/SOS microprocessor, designed for high performance floating point and integer arithmetic, with extensive real time environmental support.

The OBC has its own, redundant power converters that operate from a single 23 to 34 V power bus



  • On-Board Computers
  • Attitude and Orbit Control systems (AOCS)

Reference customers

  • Express AM (5 OBC in orbit)
  • NPO PM (Russia)